High concentration heavy metal removal by indigenous ureolytic bacteria: a comparative study with Sporosarcina pasteurii for Zn and Cd bioprecipitation

Ukachi, U. O., Omoregie, A. I., Basri, H. F., Moy, C. K.S. and Rajasekar, A. (2026) High concentration heavy metal removal by indigenous ureolytic bacteria: a comparative study with Sporosarcina pasteurii for Zn and Cd bioprecipitation. Physics and Chemistry of the Earth, 143. 104347. ISSN 1873-5193 doi: 10.1016/j.pce.2026.104347

Abstract/Summary

Heavy metal pollution from industrial activities threatens aquatic ecosystems and human health. While microbially induced carbonate precipitation (MICP) offers a promising bioremediation strategy, most studies rely on laboratory-adapted strains, such as Sporosarcina pasteurii, and provide limited comparisons with indigenous microbes under identical stress conditions. We hypothesized that an indigenous ureolytic bacterium, pre-adapted to metal-contaminated environments, would outperform S. pasteurii under suboptimal temperatures and high cadmium (Cd) and zinc (Zn) concentrations, a gap unaddressed in prior MICP literature. Here, we compare the carbonate precipitation efficiency of Comamonas sp. HMZC (B11), isolated from a polluted river catchment, with S. pasteurii at 15 °C and 30 °C using 6 mM and 8 mM Cd or Zn over 96 h. Strain B11 achieved >90% removal of both metals at 30 °C, comparable to or slightly better than S. pasteuri, and maintained 70–85% efficiency at 15 °C, with a statistically significant advantage in Zn removal under cold stress. SEM-EDS and XRD confirmed well-crystallized CdCO3 and ZnCO3 precipitates, with B11 yielding higher crystallinity. These results support the use of indigenous strains, such as B11, for biostimulation-based, site-specific remediation of heavy-metal-contaminated waters.

Item Type	Article
URI	https://centaur.reading.ac.uk/id/eprint/128515
Identification Number/DOI	10.1016/j.pce.2026.104347
Refereed	Yes
Divisions	Science > School of Archaeology, Geography and Environmental Science > Department of Geography and Environmental Science
Publisher	Elsevier
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